It has long been known that absorbent articles such as conventional taped diapers, pull-on diapers, training pants, incontinence briefs, and the like, offer the benefit of receiving and containing urine and/or other bodily exudates. Such absorbent articles can include a chassis that defines a waist opening and a pair of leg openings. A pair of barrier leg cuffs can extend from the chassis toward the wearer adjacent the leg openings, thereby forming a seal with the wearer's body to improve containment of liquids and other body exudates. Conventional chassis include a core that is disposed between a topsheet and a garment-facing outer cover (also known as a backsheet).
The outer cover can include a stretchable waistband at one or both of its ends (e.g., proximal opposing laterally extending edges), stretchable leg bands surrounding the leg openings, and stretchable side panels, which can be integral or separate discrete elements attached directly or indirectly to the outer cover. The remainder of the outer cover typically comprises a non-stretchable nonwoven-breathable film laminate. Unfortunately, such diapers do not conform well to the wearer's body during different body movements, e.g. sitting, standing, and walking due to the relative anatomic dimensional changes (which can, in some instances, be up to 50%) in the buttocks region caused by these movements. This problem is further exacerbated by the fact that one diaper typically has to fit all the wearers in a given size range.
The dimensions of the smallest and biggest wearers within a given size range can be markedly different. For instance the waist circumference at the navel can vary by 80 mm within a given size range. Also, the navel-to-back distance, which is the distance from the navel, through the crotch, and to a point on the back of the wearer that is in the same horizontal plane as the navel, can vary by about 80 mm from the smallest to the largest wearers in this same size.
In addition, it has been determined that caregivers and wearers prefer the look and feel of cotton underwear (not provided by conventional disposable diapers) for several reasons. For instance, cotton underwear include elastic waist and leg bands that encircle the waist and leg regions of the wearer and provide forces that keep the underwear on the wearer's body. Furthermore, the cotton outer cover (except in the waist and leg bands) can be stretched along the width and length directions in response to a relatively low force to accommodate the anatomic dimensional differences related to movement and different wearer positions. The stretched portion returns back to substantially its original dimension once the applied force is removed. In other words, the cotton outer cover of the underwear has low-force, recoverable biaxial stretch that provides a conforming fit to a wider array of wearer sizes than conventional diapers.
An effort has therefore begun to develop diapers that simulate the look and feel of traditional cotton underwear. However, diapers, unlike cotton underwear, are designed to receive and retain loads (i.e., bodily exudates) that are received during use while minimizing or eliminating leakage. It has been found that the downward forces resulting from these loads cause biaxially stretchable outer covers from the prior art to sag, droop, or otherwise distend to the detriment of the fit of the diaper on the wearer. Sagging is generally unsightly, and can cause leakage of the bodily exudates due to, for example, displacement of the barrier leg cuffs away from the wearer's body.
What is therefore needed is an absorbent article including an anchoring system which is capable of supporting the core assembly thereby supporting the (downward) force(s) exerted by the core assembly. Additionally, what is needed is an absorbent article capable of including a bi-axially stretchable outer cover while minimizing occurrences of sagging of the outer cover and leakage during use.